Internal-combustion engine.



G. W. HUTGHINSON.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED APB.9, 1912.

1,0333%, Patented Ju1y 23, 1912.

GEORGE WILLIAM HUTCHINSON, OF WALTON,

ZEA LAND.

INTERNAL-COMBUSTION ElilGINE.

, Specification of Letters Patent.

Application filed April 9,1912. Serial No. 689,673.

To all whom it may concern:

Be it known that I, GEORGE WILLIAM HUTCHINSON, a citizen of the Dominion of New Zealand, and. residing at lValton,

Waikato, in the Provincial District of Auckland, in the Dominion of New Zea land, have invented certain new and useful Improvements in Internal-Combustion Englnes, of which the following is a specification.

This invention relates to improvements in internal combustion engines and provides or combustion chamber which receives a fresh charge of gas, free from waste products of combustion, after the exhaust stroke of the piston.

According hereto, a main piston has a cylindrical chamber in which works a compression piston acted upon by a spring or I springs, whereby its head is normally flush with the en the main piston. When the ezatplosive e arge has been compressed beyond a certain limit the springs yield and the compression piston passes sufiiciently into the chamber to provide the amount of increased space for the explosive charge, whereby its compression is limited within certain range. The compression piston is fixed upon rods guided in the main piston and a coil spring or springs project the compression piston outwardly.

Referring to the drawings :Figurel is a sectional elevation of a cylinder and piston, showing the piston at the top of its exhaust stroke. Fig. 2 is a similar section showing the position of the piston after the charge has been drawn in, compressed, and thus prepared for firing, Fig. 3 is an inverted plan of Fig. 1, and Fig. 4 a sectional plan on line AA, Fig. 2. j

The cylinder 1 with an admission port 2, exhaust port 3, head 4, and sparking plug 5 of ordinary construction, is .fitted with a main piston 6 having a recess or compression chamber 7 wherein a compression piston 8 is slidable. The piston 8 is guided and limited in its movement by rods 9 and 10,

which pass through the head 11. ofthe piston 6; A spring 12 interposed between the piston 8 and the head 11 of the piston 6 Patented July 23', 1912.

tends to project the said piston 8 from the compression chamber 7. The piston 8 is however prevented from passing beyond the end of the piston 6 by nuts-13 upon the ends of the rods 9 and 10. The rings 14 make a tight joint between the iston 8 and the compression chamber 7, t e rings 15 make a tight joint between the piston 6 and the cylinder 1. At the top of their stroke the pistons 6 and 8 nearly close upon a projection 17 formed'upon the head 16 whereby an annular recess 18 only is left wherein waste products of combustion will be left, and wherewith the ports 2 and 3 communicate. The spring 12 is retained in position by a boss 19 formed upon the piston 8 andthe head 11, this being the position at the time of the full compression of a full charge. If a charge less than a full charge 12: drawn into the cylinder the piston 8 is correspondingly projected by the conical spring. 4

What I do claim and desire to'secure by Letters Patent or the United States is 1. An internal combustion engine comprising acylinder, a main piston therein directly connected to the crank, a compression chamber in the inner end of said piston open toward the head of the cylinder, a compression piston in said chamber acting directly on the cylinder gases, and yielding means intermediate the two pistons for urging the compression piston outward.

2. An internal combustion engine comprising a cylinder, a crank, a main piston in the cylinder connected to the crank, a compression chamber in the piston open toward the head of the cylinder, a compression piston in said chamber, means for urging the compression piston outward and ositive stops to limit the inward and outwar movement of the piston.

3. An internal combustion engine comprising a cylinder, a cylinder head providing an annular recess adjacent to the cylinder wall, the cylinder being provided with valve ports communicating-with said recess,

a main piston in the cylinder connected with no the crank. shaft, a compression chamber within the upper end of said main piston and open toward the head of the cylinder, a compression piston in said chamber, the two. pistons being arranged so that when at top stroke they are approximately in contact with the cylinder head, an adjustable stop to limit the outward movement of the compression piston, and a spring intermediate the two pistons to urge the compression piston outward.

- In testimony whereof I have signed my name to this specification in the presence of two witnesses.

, GEORGE WILLIAM HUTCHINSON. Witnesses: f

ARTHUR Lnwrr'r FERNEYHOUGH,

FLORA ELIZABETH MILNE WILSON. 

